Evaluation of structurally different benzimidazoles as priming agents, plant defence activators and growth enhancers in wheat

Priming is a valuable, facile and well-established technique used to enhance seed quality to achieve rapid germination, establishment of stress resistance and improvement of crop yields. Different natural and synthetic priming agents have been used for better crop performance and abiotic stress management. In this study, four different benzimidazoles were selected as priming agents and their comparative effects were evaluated on different biochemical attributes including total soluble protein, total oxidant status, MDA contents, antioxidant enzymes (SOD, POD) and hydrolytic enzymes (protease, estrases) compared to control. Treatments with 2-thio-1-H-benzimidazole reduced total soluble proteins and increased total oxidant status significantly but no considerable effect was observed on other parameters. Priming with 2-(4-chlorophenyl)-1-H-benzimidazole considerably increased the total oxidant status and a little improvement was observed in total soluble proteins. Seeds primed with 1-H-benzimidazole showed a noticeable decrease in the protease activity while all other priming treatments were unable to induce any detectable change compared to control. The treatment with 2-(4-methoxyphenyl)-1-H-benzimidazole induced maximum reduction in MDA contents and POD activity. Moreover, all benzimidazole priming treatments reduced mean germination time, increased germination percentage and germination rate of wheat seeds.